1. Field of the Invention
Embodiments relate to a split mask and assembly apparatus for assembling a mask frame assembly including the split mask.
2. Description of the Related Art
In general, among display devices, organic light-emitting display devices have a wide viewing angle, an excellent contrast, and a high response speed.
The organic light-emitting display devices have a stacked structure (in which an emissive layer is inserted between an anode and a cathode) and realize colors based on the principle that light is emitted as holes and electrons injected from the anode and the cathode into the emissive layer recombine. However, it is difficult to obtain high light emission efficiency with the above structure. Thus, other intermediate layers such as an electron injection layer, an electron transport layer, a hole transport layer, and a hole injection layer are selectively interposed between the electrodes and the emissive layer.
The electrodes and the intermediate layers, including the emissive layer, may be formed using various methods. One such method is deposition. In order to manufacture organic light-emitting display devices using a deposition method, a fine metal mask (FMM) having the same pattern as a pattern of a thin film to be formed is aligned on a substrate, and a raw material of the thin film is deposited to form the thin film having the desired pattern.
A split mask assembly is formed by attaching a plurality of split masks to a frame. When attaching the split masks to the frame, the split masks are pulled tight in a lengthwise direction. If the split masks are coupled to the frame while not in a taut state, waves are formed in bodies of the split masks, which decrease adhesion between the split masks and a substrate, and deteriorate precision of deposition. Thus, when attaching the split masks to the frame, the split masks are pulled tight in the lengthwise direction and then attached to the frame.